Aerogels are a composition of matter having an open cell foam structure with high surface areas and ultrafine pore and cell sizes. One commonly known aerogel is silica aerogel which consists of bonded silicon and oxygen atoms joined into long strands and then into beads randomly linked together with pockets of air between them. Silica aerogels are among the lowest density solids known and possess many potentially useful properties. However, the high production cost associated with making silica aerogels limits wide-range commercial applications, which are currently limited generally to high value military and aerospace projects.
Another type of aerogel is carbon-based aerogel, which is composed of tenuous networks of clustered carbon nanoparticles. Carbon aerogels possess some similar properties to silica aerogels, but tend to have a superior mechanical integrity. Carbon aerogels are also electrically conductive with a conductivity depending on the density and are also extremely absorptive in the infrared spectrum, reflecting only 0.3% of radiation between 250 nm and 14.3 μm. In addition, because the solid conducts heat only through narrow chains of atoms, thermal conductivity of carbon aerogels can be as low as, or lower than, that of air.
These properties of carbon aerogels lend it to numerous industrial applications including desalination, thermal and/or acoustic insulation, solar energy collection, catalyst support, and others.
Graphene is a one-atom-thick planar sheet of sp2-bonded carbon atoms that are densely packed in a honeycomb crystal lattice. Graphene is a two dimensional building material for carbon materials of all other dimensionalities. It can be wrapped up into 0D buckyballs, rolled into 1D nanotubes or stacked into 3D graphite. Graphene has excellent in-plane mechanical, structural, thermal, and electrical properties similar to carbon nanotubes.
It would be desirable, therefore, to provide a carbon-based aerogel that is a graphene, but which heretofore has not been done.